To pay
£18million for any player is a lot of money, but to pay that amount for
someone who is not the finished article is a fortune. I'm not saying that
Rio Ferdinand will not become the finished article, but Leeds are investing
in what is, as yet, unfilled potential.

He's a very good player and has all the right attributes - good on the ball,
physically strong, decent in the air and quick. But ask me to put in order
Desailly, Stam and Ferdinand, and Rio would come in third place. So Leeds
are paying a world record price for a defender who is not the best at his
job. And it is not a certainty that he will get better.

At 22, he is nowhere near his peak. People are saying he is a brilliant
player, but he is not brilliant at the moment. And he is not yet an
established international

Ferdinand has to
show he can make that step up from good player to great player, one who will
justify his huge transfer fee and wages.

But Leeds are showing commendable ambition. People might wonder why they are
buying him when they already have two excellent centre-backs in Jonathan
Woodgate and Lucas Radebe. But Radebe won't be around for ever.

If Ferdinand makes them a better team than they are, and he proves the
difference between them qualifying for the Champions League or not, then the
outlay will have been justified because the revenue on offer from playing in
Europe's top competition is unbelievable. If he signs a five or six-year
contract and they qualify for Europe every year, then the £3m a season he
will cost them can be easily offset by the cash coming in.

There are comparisons to Liverpool's decision to pay £11m for Emile Heskey
earlier this year. They knew they were paying over the odds for a player who
was not the finished article but were well aware that Heskey had all the
attributes to become a great player. I don't hear too much talk that Heskey
is not worth his fee now.

He has been on fire this season and, by the way, is still not the finished
article. He's getting better all the time and if Ferdinand improves half as
much as Heskey has done in such a short time, Leeds boss David O'Leary will
be delighted.

It was probably a blessing in disguise that Ferdinand didn't go to Euro 2000
with England. If he had played and made a mistake or two, then it might have
set back his confidence. He did all right in the recent friendly with Italy
and was unlucky that he made a couple of mistakes that led to their goal. He
won't always be punished by a strike of Gattuso's quality that night, but
will know he must eradicate those kind of lapses.

A lot of people have likened his style to mine. Well, I have to admit when I
moved south from Scotland to join Liverpool at the age of 22 I was nowhere
near the level he is at now. I think I was better on the ball but he is
10-times the better tackler than I was. I was never a physically aggressive
defender. I was okay in the air because I was 6ft 2ins but my real defensive
assets were being able to read the game and having been blessed with a bit
of pace.

As a defender, my best years probably came from 30 onwards. Certainly, for
my first five years at Liverpool all I wanted to do was get hold of the ball
and attack. What Rio has to learn - and it was something I had to learn - is
that no matter how good he is on the ball, the No1 priority of any
centre-half is defending. People say he is the best ball playing centre-half
we have and that he should be an England regular. But that is missing the
point. Being the best on the ball, comes second to being the best defender
and he has not been better than Adams, Keown or Campbell up till now.

The problem when you are good on the ball is that things come easy for you
and that's when your concentration can slip. Sometimes you don't play the
percentages because you know you are good on the ball and people expect you
to be good on the ball. You can fall into the trap of trying to be clever,
nicking the ball away in a tackle and keeping possession rather than just
concentrating on winning it.

There have been players bought for £7m or £8m in recent years who have
proved complete duds. There is no danger of that with Ferdinand because he
is already a very good player. It's just a question of him putting all the
pieces of his game together. If he does that, Leeds will have themselves a
real asset.

His departure will be a big blow for West Ham, however, despite the huge
fee. It shows they are a selling club. If they have to sell their best
players they can never really compete at the top end of the table. Other
talented youngsters like Frank Lampard, Joe Cole and Michael Carrick will be
wondering what the future holds for them.